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1983, Applied Physics B Photophysics and Laser Chemistry
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2006, Applied Physics B
1988, Applied Optics
1989, Journal of the Optical Society of America B
1988, Applied Optics
1996, Optics letters
We demonstrate high-quality FM spectra with nanosecond laser pulses. Transform-limited pulses with FM sidebands are produced by pulsed amplification of a phase-modulated cw laser. The pulses can be shifted to the UV by nonlinear mixing. We report both initial experiments on I(2) and what is to our knowledge the first observation of a far-UV transition by FM spectroscopy, at 214.5 nm. Major advantages of this method include (1) spectral resolution of the order of 0.001 cm(-1), (2) better-defined optical phase, and (3) a much smaller and more easily detected modulation frequency, ~500 MHz. The absorption sensitivity is ~10(-4), and considerable further improvement is expected.
1981, Optics Letters
2008, Applied Physics B
1992, Applied Optics
1998, Applied Physics B: Lasers and Optics
1997, Applied Optics
1998, Applied Physics B-lasers and Optics
, and its sensitivity is 7(2)×10-8 in a 1-Hz bandwidth. The corresponding minimum detectable concentration of CO2 in air has been estimated to be 1 ppm · m. This opens the possibility of a detection at ppb levels at 2 μm, where a two orders of magnitude increase in the CO2 absorption signal is demonstrated.
1991, Applied Optics
An analytical methodology is presented to calculate spectra provided by NICE-OHMS. It is based on the solutions of the equations of motion of an open two-blocked-level system performed in the frequency domain. The polychromaticity of the impinging electromagnetic field, furthermore, trapped inside a high-finesse cavity, is a potential source of induced resonances when this field interacts with a weakly absorbing nonlinear medium. These are optimal conditions to produce the well-established hole burning. However, the radio-frequency side-bands intrinsically associated with the NICE-OHMS technique require a specific treatment for describing both absorption and optical phase shift contributions. To validate the approach, numerical simulations of two transitions of C 2 H 2 in the near-infrared range are discussed. The Doppler broadening-free cross-sideband resonances have been clearly characterized under the regime of moderate electromagnetically induced saturation. Comparison to experimental data available [Opt. Express 16, 14689 (2008)] allowed us to assess the eligibility of the approach.
2012, Journal of the Optical Society of America B
2014, Journal of Quantitative Spectroscopy and Radiative Transfer
2012, Journal of the Optical Society of America B
1993, Applied Optics
2009, J Mol Spectrosc
2015, Optics express
We combine an external cavity diode laser with noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) using current modulation. With a finesse of 1600, we demonstrate noise equivalent absorption sensitivities of 4.1 x 10<sup>-10</sup> cm<sup>-1</sup> Hz<sup>-1/2</sup>, resulting in sub-ppbv detection limits for Doppler-broadened transitions of CH<sub>4</sub> at 6132.3 cm<sup>-1</sup>, C<sub>2</sub>H<sub>2</sub> at 6578.5 cm<sup>-1</sup> and HCN at 6541.7 cm<sup>-1</sup>. The system is used for hydrogen cyanide detection from sweet almonds.
2002
2011, Journal of the Optical Society of America B
1988, Applied Optics
1999, Terahertz Spectroscopy and Applications
2009, Optics Express
1994, Laser Techniques for State-Selected and State-to-State Chemistry II
1992, Applied Optics
2010, Optics Express
2015, Applied Physics B
2011, Journal of Applied Physics
2014, Optics Letters
2001, Journal of The Optical Society of America B-optical Physics
1995, Optics …
We describe a compact, economic and versatile diode laser system based on commercial laser diodes, optically stabilized by means of feedback from a diffraction grating. We offer detailed information which should enable the reader to copy our set-up which uses only easily ...
2005, Optics Express
2009, The Journal of Chemical Physics
2015, Physical Review A
1999, Chemical Physics Letters
Journal of Lightwave Technology
1994, Progress in Quantum Electronics
2006, Journal of Optics A: Pure and Applied Optics
2000
1988, Journal of Molecular Spectroscopy
1991, Journal of the Optical Society of America B
1999, Advanced Semiconductor Lasers and Their Applications
2009, Quantum Sensing and Nanophotonic Devices VI
2000, IEEE Transactions on Instrumentation and Measurement
2000, International Topical Meeting on Microwave Photonics MWP 2000 (Cat. No.00EX430)
1999
Abstract InGaAs quantum-well complex-coupled DFB lasers with gain coupling induced by vertical emission are demonstrated. Continuous-wave operation of these lasers at room temperature provides single-mode emission at a wavelength around 980 nm. A spectral linewidth as narrow as 15 MHz and a side-mode suppression ratio larger than 40 dB are obtained. The use of this gain coupling mechanism permits to reduce the influence of the regrown interface quality on the laser performance.
2004, Interferometry XII: Techniques and Analysis